Coral Recruits Surveys

Overview

The Coral Recruit dataset contains juvenile coral observations collected at UVS stations using standardized quadrat surveys. Each 50-meter transect includes ten 0.5 × 0.5 m quadrats, placed at fixed 5-meter intervals along the transect line, for a total surveyed area of 2.5 m² per station.

Data are stored in two tables:

• uvs.recruits_stations — One row per station with metadata and summary metrics
• uvs.recruits_observations — One row per recruit observation, including genus, size, and quadrat

All records are linked by ps_station_id. Taxonomic fields include accepted_name and accepted_aphia_id, standardized to the genus level.

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Tables

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Stations (uvs.recruits_stations)

This table stores metadata and summary metrics for each coral recruit survey station. Each row corresponds to a depth-stratified UVS site where coral recruits were surveyed using a series of ten 0.25 m² quadrats (total area = 2.5 m²). Fields include spatial context, survey effort, and total recruit counts and density.

Table 1: Schema for uvs.recruits_stations: metadata and summary metrics for coral recruit stations

Field	Type	Required	Description
ps_station_id	STRING	true	Unique station ID (ps_site_id_depth).
ps_site_id	STRING	true	Foreign key to uvs.sites.
exp_id	STRING	true	Expedition ID (ISO3_YEAR).
method	STRING	true	Survey method (uvs).
protocol	STRING	true	Survey protocol (coral_recruits).
divers	STRING	true	Divers who conducted the recruit survey.
region	STRING	true	Region name.
subregion	STRING	true	Subregion name.
locality	STRING	false	Optional local feature (e.g., reef, bay).
latitude	FLOAT	true	Latitude of station (decimal degrees).
longitude	FLOAT	true	Longitude of station (decimal degrees).
date	DATE	true	Date of coral recruit survey.
time	TIME	true	Start time of the survey.
depth_m	FLOAT	true	Average station depth (m).
depth_strata	STRING	true	Depth bin: supershallow, shallow, deep.
habitat	STRING	true	Habitat type.
exposure	STRING	true	Exposure type.
n_quadrats	INTEGER	true	Number of quadrats surveyed (typically 10).
quadrat_area_m2	FLOAT	true	Area of each quadrat in m² (typically 0.25).
survey_area_m2	FLOAT	true	Total area surveyed (e.g., 2.5 m²).
total_count	INTEGER	false	Total number of coral recruits recorded.
count_m2	FLOAT	false	Recruit density (individuals/m²).
notes	STRING	false	Optional QA or field notes.

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Observations (uvs.recruits_observations)

This table contains one row per juvenile coral colony observed within a quadrat. Records include genus-level identification, maximum diameter (cm), and quadrat number. All observations are linked to a survey station via ps_station_id.

Table 2: Schema for uvs.recruits_observations: coral recruit observations by quadrat

Field	Type	Required	Description
obs_id	STRING	true	Unique observation ID (e.g., FJI_2025_rec_JSD_0001).
ps_station_id	STRING	true	Foreign key to uvs.recruits_stations.
diver	STRING	true	Name of the diver who recorded the observation.
station_label	STRING	true	Field-assigned stratum label (e.g., shallow, deep).
depth_m	FLOAT	true	Recorded depth (m) at which the transect was conducted.
quadrat	INTEGER	true	Quadrat number (1–10) at fixed intervals along the transect.
accepted_name	STRING	true	Genus-level scientific name (Genus sp.) of the coral recruit.
accepted_aphia_id	INTEGER	true	WoRMS AphiaID — foreign key to taxonomy.corals.
diameter_cm	FLOAT	true	Maximum colony diameter (cm), measured in the field.
notes	STRING	false	Optional comments or QA annotations.

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Density (uvs.recruits_density)

This table contains station-level summaries of coral recruit density by taxon, derived from raw counts in replicate quadrats along UVS transects. Each row represents a unique combination of ps_station_id and coral taxon, with recruit density standardized to individuals per square meter.

Coral recruits are defined as juvenile colonies <5 cm in maximum diameter, recorded within 10 haphazardly placed 0.25 m² quadrats (total survey area = 2.5 m² per transect). Recruits are typically identified to genus, and the standardized accepted_name and accepted_aphia_id fields represent the minimum taxonomic resolution confidently assigned to each observation.

Taxonomic information is joined from taxonomy.corals, and all entries are linked to the parent survey station via ps_station_id.

Table 3: Schema for uvs.recruits_density_by_taxa: coral recruit density summaries by station and taxon

Field	Type	Required	Description
ps_station_id	STRING	true	Unique station ID (ps_site_id_depth).
accepted_name	STRING	true	Standardized taxon name (typically genus).
accepted_aphia_id	INTEGER	true	WoRMS AphiaID — foreign key to taxonomy.corals.
family	STRING	true	Family of the coral taxon.
growth_form	STRING	false	Typical growth form of the genus (e.g., branching, massive, encrusting).
region	STRING	true	Region name.
subregion	STRING	true	Subregion name.
locality	STRING	false	Optional local feature (e.g., reef, bay, cove).
depth_m	FLOAT	true	Mean depth (m) of the station.
depth_strata	STRING	true	Depth bin: supershallow, shallow, or deep.
habitat	STRING	true	Dominant habitat type at the station.
exposure	STRING	true	Wave/wind exposure at the station.
total_count	INTEGER	false	Total number of recruits observed across all quadrats.
density_m2	FLOAT	false	Recruit density (individuals/m²), standardized by total quadrat area (2.5 m²).